In a large bowl, whisk together 1/2 cup maple sugar, cornmeal, flours baking powder, baking soda, and salt. Use a wooden spoon to make a well in the center.

In a small bowl, whisk together the yogurt, milk, butter, vanilla and egg. Add to dry ingredients, stirring just until combined.

Topping

In a small bowl, combine maple sugar and white cornmeal

Lightly coat a 12 cup muffin tin with cooking spray and divide batter evenly between each cup. Sprinkle sugar/cornmeal mixture evenly over muffins. Bake for 17 minutes or until a toothpick inserted in center comes out almost clean. Carefully remove the muffins from the baking pan and let cool on a wire rack.